Refrigerating apparatus



May 21, 1929. B. THCIJENS 1,713,934

REFRIGERATING APPARATUS Filed Oct. 9 1925 2 Sheets-Sheet 1 ATTORNEY May 21, 1929. B. THOENS REFRIGERATING APPARATUS Filed Oct. 9. 1925 2 Sheets-Sheet 2 INVENT ATTORNEY Patented May 21, 1929.

Buncmp THOENS, or

PATENT OFFICE.

NEW YORK, N. "2., nssxenon or ONE-HALF 'ro Bunomn M. 'rnonns, on NEW YORK, N. Y.

. REFRIGERA'I'ING APPARATUS.

Application filed hctober 9, 1925. Serial No. 61,553.

In Patent No, 1,369,365, granted to me February 22, 1921, is disclosed and claimed a method of refrigeration, and in Patent No. 1,369,366, granted to me the same day, is described and claimed an apparatus for practicing such method. The present-invention likewise relates to refrigerating apparatus and has for its object the improvement of the apparatus disclosed in my prior apparatus patent above referred to whereby the method previously patented by me can be carried outwith greater ease and facility.

My improved method is a combination of the well known vacuum and absorption methods of refrigeration but possesses advantages peculiar to neither of these systems and avoids disadvantages incident to both. Thus the use of acids as in vacuum systems is avoided and also the use of expansion valves. In addition, the heat supplying mechanism of the adsorption system is avoided. Furthermore, the refrigerant is at low pressure, there being little tendency consequently for the refrigerant to escape from the system. The danger of explosion is also minimized and danger of decomposition of the refrigerant practically eliminated. I have found it desirable, in practicing my patented inventions, to provide certain automatically operating devices for controlling the operation of the machine, these controlling instrumentalities not beingessentialto the successful practice of such inventions but being desirable in that they permit closer regulation of the temper-- atures and pressures, avoiding considerable hand adjustment and supervision. The object of the present invention therefore, is to provide an apparatus whic is more completely automatic and self-regulating in all its phases. Various novel liquid refrigerant flow regulating devices have been provided and satisfactory forms of such devices are herein illustrated and described in detail. The invention is not of a limited nature, however, and, without departing-from its spirit and scope, modifications of the design and arrangement of the component elements of the improved apparatus may be made to suit conditions.

vIn the drawings: V

Figure 1 illustrates partly in elevation and partly in section a substantially complete apparatus for practicin my method OfdGfI'lgeration, the improve regulating devices being incorporated therein;

Figures 2 and 3 are sectional views through two of the regulating devices; and

Figure 4 is a sectional view through a regulating device which may be substituted for that shown in Figure 3.

The apparatus of the present invention bears, in its major features, a close resemblance to the apparatus disclosed in my prior patents, and the method of operation of the present apparatus is in substance the same as that ofthe method of operation of the apparatus previously patented. Thus re frigerant gas is drawn from the .top of a vacuum or cooling tank A through a pipe 10 by a suction pump B and is discharged by this pump into the bottom of absorber C, pipe 12 connecting the outlet of the pump and the absorber. A cold weak solution from the vacuum tank A flows downwardl by gravity from this tank and is also disc iarged into the bottom of the absorber, this stream of refrigerant flowing by way of pipe 13, heat exchanger D and pipe 14. The mouth of pipe 14 is closely adjacent to the mouth of pipe 12 and the gas from the pump is quickly absorbed by the weak solution as the two intermingle in the absorber. The solution in the upper part of the absorber, which is now relatively strong due to the absorption of the gas, is drawn upwardly to the vacuum tank by way of pipe 15, heat exchanger D and pipe .16, the flow taking place due to the difference in pressure within the absorption and vacuum tanks.

The body of the cold. relatively weak re-. frigerant in solution in'the vacuum tank is indicated at S and while this tank itself is a cooling unit which .may be sufficient for cooling purposes in certain instances, in the case of household refrigerating plants pipes 17 are provided through which the cool so- 'lution may be passed to refrigerating coils located in a refrigerator If desired, a pump (not illustrated) may be utilized to insure such circulation, as suggested in my prior patents,

To remove the heat of absorption from the absorption tank C, cooling water is circulated in a stream parallel to, but out of contact with, the rising stream of refrigerant in the ab-. sorber, the numeral" 18 indicating the water inlet pipe and the numeral 19 indicating the water outlet pipe.

It will be seen that the absorber C is substantially rectan ular in section and that the stream of refrigerant flowing upwardlyfor breaking up the stream of in therethrough follows a tortuous passage to the right of the zigzag division plate and that the cooling water follows a tortuous passage downwardly on the left hand side of th1 s plate. Battle plates 21 extend into the hon Zorltally disposed pockets of the division plate and cause the streams of fluid to enter these pockets to their full depth. Toward the top of the absorber the stream of refrigerant passes into a vertically upwardly extending conduit or passage 22, flows laterally and 1s then discharged into a chamber 23 from which it escapes into pipe 15. I

The heat exchanger D is of the same characteras the absorber in its mechanical construction, having, however, no upper compartment such as compartment 23 of the absorber, and being somewhat smaller in slze. Thus it is provided with a zigzag division plate 20 and a series of bafile plates 21' extending horizontally into the horizontal pockets of the division plate.

The vacuum tank is preferably cylindrical device in its uper end for owing strong or concentrated solution so that the refrigerant gases may be more freely vaporized. Thus there is suspended from the discharge end of at the bottom. This hood in turn supports perforated pans or trays 25. It is readily seen that the incoming stream of refrigerant is broken up into a number of smaller streams by the upper pan 25 and that this action is repeated for each of the resulting smaller streams by the lower pans. A large surface of refrigerant is thereby exposed to the action of the pump Band evaporation is carried on at a rapid rate.

or regulating the flow of cold weak solution downwardly through pipe 13, a measuring device E is provided, this device being fully illustrated and described in my co-pending application Serial No. 589,455 filed Sep tember 20, 1922. Briefly stated, it comprises a cylindrical casing 26 which contains a rev oluble, tightly fitting plug 27 which may be constantly or intermittently rotated at uniform speed by some power device. The re- A flows by gravity downfrigerant from tank wardly to plug 27, and, .due to rotationof this plug at stated intervals, is allowed to pass. Gas is introduced into conduit 13 below plug 27 by pipe 28 which opens into the top of the absorber, and as lug 27 rotates in the direction of the arrow Small igure 1). quantities of this gas, trapped in the plug bemg at a much higher pressure than that which f Olftillll; in the vacuum (fimkl A ancll1 hence above p u- 2 ,esca eupwar t rou i e29 and are discharg gd into the body t l el rigerant Pipe 29 prevents dischrge of this gas u wardly through pipe 13, which would blow out the refrigerant in this ipe and would pre-' vent accurate operation 0 the measuring de pipe 16 a hood 24 closed at the top and open vice E. The gas is necessary to balance the pressures and allow liquid to flow by gravity into tank C'. The rotating plug takes the place of a pump and transfers liquid from a chamber at low pressure to one at a higher pressure with a minimum expenditure of power. At the same time, by runnlng the plug at constant speed, a measured quantity of liquid can be delivered.

The gravity feeder E discharges constant amounts of cold weak solution from the vacuum cooler through the heat exchanger into the absorber, while an equal amount of strong warm solution passes from the absorber through the heat exchanger to the vacuum cooler. In the heat exchanger the two solutions flow in opposite directions so that the cold weak solution enters the absorber relatively warm and the warm strong solution enters the vacurn cooler relatively. cold. The quantity of refrigerant flowing depends on the difference of pressure inthe vacuum cooler and the absorber. To accurately regulate, however, the ratev of flow of refrigerant, the cold strong solution is caused to flow on its way upwardly through pipe 16 through a regulator F which is shown in detailin Figure 3.

This regulator comprises simply a vertically arranged cylinder having a plunger therein with spaced cylinder wall fitting portions 36 and 37. he annular groove between these portions constitutes a passage for the flow of refrigerant when it is in alignment either wholly or partially with the inlet port 38 and the outlet port 39 of the casing 35. The plun er, therefore, constitutes a valve and it wil be seen that the flow of refrigerant will be obstructed if the plunger moves downwarclly from a central position. The plunger rests upon a sprin 40 and is provided with a hollow downwardly extending tubular stem 41 at the lower end of which an open pan 42 is secured. The stem. 41 is perforated at a3 so that the gas in the upper end of the absorption may flow to pipe 28 and thence to the gravity feeder E, as previously pointed out, pipe 28 having its lower terminal in a plug 44 which closes the upper end of casing 35 and pipe 41' extending through valve members 36 and'37 as can be seen from Figure 3, thus also perfectly balancing the plug valve.

- The ofperation of thisregulator F is as follows: I more liquid flows out from the absorberat the top than enters it at the bottom, the liquid level in. chamber 23 will be lowered. he pan 42, which is constantl full of rerigerant, and which exactly h alances the sprin 40 under normal conditions, will, therefore descend, and as the pan descends the valve 36 will partially obstruct ports 38 and 39 thus diminishing the flow to the vacuum tank. The and keeps the refrigerant from too rapid movement at all times.

adjustment'is automatic It will be apparent also that the temperature in the vacuum cooler at which the apparatus works should be capable of variation to suit conditions. A lower temperature requires a higher-vacuum to-dissociate the gas from the liquid, and gas at a higher vacuum is less in weight than the same gas at a lower vacuum, requiring less weak solution for retion of the refrigerant when the machine operates under a higher vacuum, a regulator G is utilized, this regulator being mounted upon the top of the vacuum tank and acting upon the stream of cold strong solution just before its discharge into the vacuum tank.

This regulator is clearly illustrated in Figure 2. It comprises essentially a casing 48 having a plug or valve member 49 slidably mounted therein, this member being grooved midway of its length to provide a passageway for the solution between the inlet port 50 and the discharge port 51 of the casing. Obviously, movement of the valve or plug 49 from" a central position toward the right end will diminish the flow of liquid through the regulator,,and vice versa. The left hand end of the plug 49 is subjected to the pressure of the absorber, a bypass or duct 52 leading from this end of the casing to a point adjacent the inlet ort 50. A similar duct 53 brings the sham er at the right hand end of the valve plug 49 into communication with the discharge port 51. A spring '54 acts against the right hand end of plug 49 and the tension in this spring may be adjusted to suit conditions by means of set screw 55.

The sliding valve plug, regulating the sizes of the inlet and outlet ports 50 and 51, has, therefore, on one end the absorber pressure and on the opposite end the spring 54 and communication with the vacuum tank. If, therefore, the vacuum is increased the opening or passage is diminished, the plug sliding to the right (Figure 2) and the amount of fluid flowing being thereby cut down. If the absorber pressure should go higher the result would be the same, the plug being forced to the right by the increased pressure on its left hand end. The flow of cold stron refrigerant into the vacuum tank is, therefore, doubly regulated, that is, it is regulated so that increasing the vacuum through speeding up the pump B cannot cause increased rapidity of flow of refrigerant and is also so regulated that the liquid levels in the absorption andvacuum tanks are maintained constant. With the two regulating devices F may operate under varying conditions without manual adjustment of valves.

If desired, the regulator H illustrated in Figure 4 may be substituted for the regulator F shown in Figure 3. The control of the flow of fluid upwardly through pipe 16 is unaffected by this change but it will be observed that additional means is provided in this modified form of regulator for controlling the flow of fluid downwardly through pipe 13. Thus the sliding plug is provided with two grooves instead of one as in Figure 3, the cold weak solution flowing through the upper groove and the strong solution flowing through the lower groove, the directions of flow being indicated by, the arrows in Figure 4. Ohviously, upward movement of the plug will allow increased flow through pipe 16 but will retard the flow through pipe 13. Downward movement of the plug will result in increased flow through pipe 13 and decreased flow through pipe 16,

Other modifications of the device may obviously be adopted and the invention is not limited to the precise mechanical details which are herein described, and illustrated in the drawings.

Suitable pressure gauges 60 and 61 are provided, together with charging and drain valves. Thus a valve is shown at. 62 through which "all of the liquid in the system may be withdrawn anda second valve is shown at 63 through which the system may be charged. Additional cut-off valves 64, 65 and 66 are also provided.

In charging the system, valves 65 and 66 are closed and the vacuum pump B set in motion. In a short time a partial vacuum is created in the vacuum tank A and a solution of ammonia may be drawn into this tank from a suitable receptacle by means of a hose attached to pipe 67, valve 63 being open. The gauge glass 68 Will indicate when the proper amount of liquid has been drawn into the the dissociation of gas from the liquid in the vacuum tank, the solution in the tank becoming, therefore, cold and being weakened while the solution in the absorber becomes warm and is strengthened. One pound of gas dissociated from its solution abstracts about 800 B. t. u. while during absorption it will liberate about 800 Blt. u. in the absorber, this heat which is thus liberated being removed by the cooling water or by air cooling means if desired. After the solution in the vacuum cooler has been lowered in temperature to the desired point, the valves 65 and 66 are opened and the system is then free for the circulation of refrigerant, as previously outlined. T

quantities of -l-lavingthus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A refrigerating apparatus including in combination, frigerant is evaporated from solution, an absorption tank, means for withdrawing re frigerant vapor from the vacuum tank and introducing it into the absorption tank, a conduit for conducting liquid refrigerant solution from the absorption tank to the vacuum tank, and means for automatically maintaining the flow of liquid through said conduit constant in spite of changes in the pressure difference existing in said tanks.

2. A refrigerating apparatus including in combination, a vacuum tank, an absorption tank, means for withdrawing refrigerant vapor from the vacuum tank and introducing it into the absorption tank, means for conducting refrigerant in solution from the vacuum tank to the absorber, means for conducting refrigerant in solution fromjthe absorber to the vacuum tank, and means for automatically controlling the flow through said last mentioned means in accordance with the li uid level in said absorption tank.

3. i refrigeratin apparatus including in combination, an a sorption tank having means for forcing substantially constant quantities of gaseous refrigerant and refrigerant in weak solution thereinto and for removing refrigerant in strong solution therefrom, and a device for automatically controlling the flow of strong solution from the absorber so that the outflow is substantially equal to the inflow in spite of change in the pressures causing said flow.

4. A refrigerating apparatus including in combination, an absorption tank having means for forcing substantially constant quantities of gaseous refrigerant and refrigerant in weak solution thereinto and for removing refrigerant in strong solution there from, and a device for automatically con-' trolling the flow of strong solution from the absorber so that the outflow is substantially equal to the inflow, said device having an operating member whose position varies with the liquid level in the absorber.

5. A refrigerating apparatus including in combination. an absorption tank having means for forcing substantially constant gaseous refrigerant and refrigerant in weak solution thcreinto and a conduit for conducting a strong solution of refrigerant therefrom. and means for auto matieally regulating the outflow of strong solution comprising a valve in said conduit and a member within the tank governed by rise and fall of the level of the liquid therei n, s21 id member being operatively connected to said valve.

6. A refrigeratin apparatus including in combination, an a.

eorption tank having a vacuum tank in which a re' means for introducing gaseous refrigerant and refrigerant. in weak solution thereinto and a conduit for conducting a strong solution of refrigerant therefrom, and means for automatically regulating the outflow of strong solution comprising a valve in said conduit, a stem for said valve projecting into the tank, and a pan secured to said valve stem and normally filled with refrigerant, said panbeing partially immersed in the liquid in the tank and adapted to rise and fall with theliquid level to thereby operate the valve. i

7. A refrigerating apparatus including in combination, a vacuum tank, means to withdraw refrigerant in gaseous form from the tank, a conduit for introducing liquid into the tank, and means for regulating the inflow of liquid into the tank through said conduit in inverse relation to the pressure differential between said conduit and said vacuum tank. r

8. A refrigerating apparatus including in combination, a vacuum tank, a suction device for withdrawing refrigerant in gaseone form from said tank, a conduit for introducing liquid refrigerant solution into said tank, and valve means for regulating the in- I flow of liquid through said conduit, said valve being automatically operated by the pressure differential between said conduit and vacuum tank to maintain a substantially constant flow of liquid.

9. A refrigerating apparatus including a vacuum tank, means for withdrawin gaseous refrigerant from the tank, a con uit for introducing refrigerant in liquid solution into the tank, and means for automatically restricting the flow of liquid into the tank when the difference between the pressures existing in the tank and conduit increases.

10. A refrigerating apparatus including in combination, a vacuum tank in which a refrigerant is evaporated from solution, an absorber, means for withdrawing gaseous refrigerant from the tank and introducing it into the absorber, means for conducting refrigerant in solution from the absorber to the vacuum tank, and means for automatically maintaining the liquid in the absorber at a substantially constant level.

11. A refrigerating apparatus including in combination, a vacuum tank in which a refrigerant is evaporated from solution, an absorber, means for withdrawing gaseous refrigerant from the tank and introducing it into the absorber, means for withdrawing measured quantities of refrigerant in solution from the tank and introducing it into the absorber, and means for returning a meas ured amount of refrigerant in solution from the absorber to the vacuum tank.

In testimony whereof I hereunto aflix my signature.

- BURCHARD THOENS. 

